handle comments and empty lines directly in the parser's main loop

note that comment handling is currently a bit too simplistic as stuff
like

FOO
'-- hello' /

won't work. as far as I can see, this is not different from the state
before this patch, though.
don't enter the parsing main loop if the leftover-from-last time keyword does not have any records
Parser::parseState(): remove the 'verbose' debugging facility

This one could only be enable by modifying the source code. If such
debugging output is needed, it should be directly added via std::cout
and removed it before proposing the PR...
Well(Injection|Production)Properties: adapt it to the naming and style conventions of the rest of the module

this patch only changes the conventions which are internal to the
code, i.e., users of these classes do not need to be adapted...
Make MULTREGT work for NNC.

The region multipliers are no longer added  to the cartesian logical
MULT[XYZ] structure. Instead a new method
getRegionMultiplier(globalIndex1, globalIndex2,FaceDir) is added that
return the multiplier between globalIndex1 cell and globalIndex2 cell.
The face direction is added to support directional dependent MULTREGT
input. This implementation of MULTREGT also supports restricting the
multipliers to only apply for NNC or NONNNC.
address the review comment of #373
add the NOGRAV flag keyword

according to [at] bska this is from Frontsim and should be supported.
ParserKeyword: make the exception messages more verbose

mostly, include the keyword names, so that the user can fix these
errors without using gdb. (Not that I mind gdb, but I have been told
that gdb is a big no-no. ;)

(this patch also fixes a few typos...)
Merge pull request #380 from andlaus/multregt

Multregt
Merge pull request #235 from andlaus/add_NOGRAV

add the NOGRAV flag keyword
Merge pull request #344 from andlaus/more_useful_exception_messages

ParserKeyword: make the exception messages more verbose
add a "Transmissibility" unit

this is required because Eclipse is inconsistent when specifying
transmissiblities: the only difference between transmissibilities in
metric and field units is that the pressures are in bars instead of
PSI, i.e. the numerator for metric units is still given in centi-Poise
times bbl. This makes it impossible to specify the transmissibilities
in terms of their constituting bits...
add the NNC keyword

this can be used to directly specify transmissibilities for
NNCs. Note that this keyword is quite a mess for everything after
the mandatory items according to the documentation.
add the TRAN[XYZ] keywords

these are required to directly specify the transmissibility of
neighboring connections.
add grid properties for the TRAN[XYZ] keywords
Merge pull request #382 from andlaus/transmissibility_input

Transmissibility input
Merge pull request #339 from andlaus/low_level_improvments

Low level improvments
get rid of the 'strict parsing' concept

this is the 'Joakim-style' variant of the patch, i.e., an exception
will always be thrown if an unknown keyword is encountered.
Merge pull request #347 from andlaus/always_parse_strictly

get rid of the 'strict parsing' concept