[idrac] add enable_ipmi, tweak error message

minimal ipmi configuration support: enable_ipmi action to enable ipmi over LAN support

be more descriptive when jnlp fails on iDRAC6 for old firmware
Merge pull request #5 from nferch/ipmi

[idrac] add enable_ipmi, tweak error message
sane timeout for HTTP connections
don't fetch ipmiKey info

don't fetch ipmiKey info, causes the HTTP request to hang on some configurations
version 0.3.7
Merge pull request #6 from nferch/ipmi

bugfixes, version 0.3.7