Improve install instructions

[fulldecent]

Install instructions at http://solidity.readthedocs.io/en/develop/installing-solidity.html includes many install options. The first recommendation is:

npm install -g solc

The usage instructions are at http://solidity.readthedocs.io/en/develop/using-the-compiler.html and begin with:

solc

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If you buy a new Mac, then install and run Xcode, per instructions, and then run those two commands you will get:

command not found: solc

[axic]

Please note the text above the npm install command which reads:

It also contains a commandline tool called solcjs, which can be installed via npm:
npm install -g solc

It mentions that the installed tool will be called solcjs. It may be a bit confusing - do you have any suggestions to improve the wording? A pull request would be welcome if you are interested.

[fulldecent]

Thanks for explaining. Here is a brief pair of PRs.

[fulldecent]

Merged. Fixed in c7632fc