fix(less): Add less compile target files as options.

[nmorenor]

Right now the LESSPlugin will compile all the .less files trying,
althogh the less compiler is silently failing and sending just a stacktrace.
This change allow you to send a 'compile-targets' array with the list of .less
files that should be compiled.
The issue is that some .less files are trying to use a not available variable
at the scope of the file, the less files could contain a set of files with all
the imports. If we tell the compiler to just compile these files we get the desired
behaviour, your dist directory get the css files.

There could be improvements over this change, like displaying a better less compiler
message so that you know why your files did not compile. Another improvment is the fact
that the less @import inside the node_modules are not resolved by the less compiler,
perhaps we could add a special variable that is replaced on this files at compile time
to resolve the path of the node_modules.

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[nmorenor]

I signed it as part of Genuitec’s CLA

[nmorenor]

This could be an example on how you'll specify the compile-targets

module.exports = function(defaults) { return new Angular2App(defaults, { vendorNpmFiles: [ 'systemjs/dist/system-polyfills.js', 'systemjs/dist/system.src.js', 'zone.js/dist/**/*.+(js|js.map)', 'es6-shim/es6-shim.js', 'reflect-metadata/**/*.+(ts|js|js.map)', 'rxjs/**/*.+(js|js.map)', '@angular/**/*.+(js|js.map)' ], lessCompiler: { 'paths': ['src/app/less', 'node_modules/bootstrap-less' ], 'compile-targets' : [ 'src/app/less/main.less' ] } }); };

As a side note:
By having the paths: node_modules/bootstrap-less allow you to import less files from inside this module, having an import like @import "bootstrap/variables.less";

[nmorenor]

After a second thought, maybe the change should be the other way around. Since Angular 2 is component based and you can have a css per component, perhaps the lessCompiler option should be to set the paths to exclude.

lessCompiler: { 'paths': ['src/app/less', 'node_modules/bootstrap-less' ], 'exclude-targets' : [ 'src/app/less/**/*.+(less)'] } }); }

That will allow you to have all your less files under src/app and allow you to use .less files for your components, compiling them using imports like, @import "variables.less", making less to look for imports in one of the 'paths' parameter, in this case src/app/less/variables.less

[nmorenor]

I signed it!

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CLAs look good, thanks!

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